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Flashcards in SANS Anesthesia Deck (8)
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1
Q

Seorang pasien memperlihatkan meningioma parietal ukuran kecil pada reseksi, memiliki preoperative INR sebesar 1.5. Berapakah kemungkinan persentase bahwa tranfusi 2 unit FFP dapat menormalkan INR nya ?

A. 50 %
B. 25 %
C.

A

C.

2
Q

Seorang wanita sehat mengalami aneurysmal subarachnoid hemorrhage. Kadar troponin ketika dirawat adalah 1.4ng/ml dan transthoracic echocardiography memperlihatkan sebuah ventricular ejection fraction kiri sebesar 15% dengan hypo-kinesis apical berat. Mekanisme patofisiologis yang paling mungkin dari disfungsi cardiac tersebut adalah :

A. Catecholamine-induced myocardial stunning
B. Multi-vessel coronary artery spasm
C. Thrombolitic coronary artery occlusion
D. Microvascular myocardial ischemia
E. Tachycardia induced cardiomyopathy

A

A. Catecholamine-induced myocardial stunning

The correct answer is Catecholamine-induced myocardial stunning.

This patient has features of a neurogenic stress cardiomyopathy of the Tako-tsubo variety. There are multiple theories underlying the pathophysiology of neurogenic stress cardiomyopathy. The most likely mechanism of neurogenic stress cardiomyopathy is related to the significantly elevated catecholamines post aneurysm rupture. In the SAH beagle-dog model, perforating the basilar artery with a microcatheter inserted through the femoral artery causes catecholamines to increase abruptly 5 minutes after SAH onset.5 The peak values of CK-MB and troponin T correlate positively with the peak values of norepinephrine and epinephrine, suggesting that elevated sympathetic activity in the acute phase of SAH contributes to the development of cardiac dysfunction.

Thrombotic coronary artery occlusion is unlikely as the troponin elevation is not in keeping with severity of the ventricular dysfunction. Furthermore this patient has no previous risk factors for coronary artery disease. Multi-vessel coronary artery spasm is unlikely. In studies by De Chazal, Chang and Yuki no evidence of coronary spasm was seen. Microvascular ischemia is unlikely based on one canine SAH study with myocardial contrast echocardiography. A cardiomyopathy can be induced with prolonged tachycardia, however the Tako-tsubo pattern is atypical.

3
Q

Cerebral-salt wasting syndrome (CSW) dapat dijelaskan sebagai berikut :

A. Iso-osmolar, euvolemic hyponatremia
B. Hypo-osmolar, hypervolemic hyponatremia
C. Hypo-osmolar, hypovolemic hyponatremia
D. Hypo-osmolar, euvolemic hyponatremia
E. Hyperosmolar, hypovolemic hypernatremia

A

C. Hypo-osmolar, hypovolemic hyponatremia

The correct answer is hypo-osmolar, hypovolemic hyponatremia.

CSW is thought to be caused by increased secretion of natriuretic peptides (likely mediated by activation of the sympathetic nervous system) leading to excessive excretion of sodium in the urine. High intra-tubular sodium content secondarily provokes an osmotic gradient that drags water into the urine. Consequently, CSW is associated with intravascular volume contraction. Therefore CSW is characterized by hyponatremia (Na+

4
Q

Selama pembuatan sebuah burr hole untuk deep brain stimulator, seorang pasien yang sadar menunjukkan gejala batuk dengan onset mendadak, hypotensi, dan hypoxia. Presentasi klinis tersebut menunjukkan komplikasi manakah :

A. Intracranial hemorrhage
B. Aspiration pneumonia
C. Air embolism
D. Tension pneumocephalus
E. Seizure activity
A

C. Air embolism

During creation of the burr hole in awake patients, sudden vigorous coughing may be a sign of venous air embolism. Other signs are unexplained hypoxia and hypotension. Early detection may be possible with precordial Doppler monitoring. The overall incidence of venous air embolism as detected by a precordial Doppler ultrasound has been reported to be 4.5%. Hooper et al. in their small study of 21 patients noted 1 venous air embolism (1 of 22 lead insertions), and the important predictors were patient positioning and the occurrence of coughing.

5
Q

Efek samping dari infus dexmedetomidine apakah yang paling membahayakan pada pasien ICU ?

A. Inhibisi dari locus ceruleus
B. Bradycardia
C. Systolic hypertension
D. Depresi pernafasan
E. Intracranial hypertension
A

B. Bradycardia

Bradycardia is a common side effect of dexmedetomidine. Patients who develop a 30% decrease in heart rate may be particularly at risk for severe bradycardia. Side effects of dexmedetomidine may not reverse quickly after discontinuation. Caution is recommended in the use of dexmedetomidine in patients with a cardiac history.

Dexmedetomidine can cause hypotension, but does not cause hypertension. The effects of dexmedetomidine may lag onset and cessation of dosing. As a selective alpha 2 agonist, dexmedetomidine causes little respiratory depression and can be used for sedation in non-intubated patients. While not thoroughly investigated in humans, animal studies suggest that dexmedetomidine does not increase intracranial pressure.

6
Q

Manakah dari obat-obatan berikut yang menyebabkan penurunan terbesar pada cerebral metabolic rate of oxygen (CMRO2) :

A. Sufentanil
B. Sodium thiopental
C. Ketamine
D. Diazepam
E. Propofol
A

B. Sodium thiopental

All the agents listed cause a dose-dependant decrease in CMRO2; however, sodium thiopental is the only agent listed that decreases CMRO2 to the minimal level required to maintain cellular homeostasis.

7
Q

Manakah dari opioid berikut yang memiliki onset puncak paling lambat ?

A. Sufentanil
B. Fentanyl
C. Alfentanil
D. Remifentanil
E. Morphine
A

E. Morphine

Compared to the synthetic opioids, morphine is relatively hydrophobic and crosses the blood brain barrier much more slowly. The onset of all the other opioids listed is relatively fast—less than 10 minutes to peak effect. By contrast, morphine peak effect takes approximately one hour.

Alfentanil and remifentanil are fast equilibrating opioids with peak onset (or equilibration half-lives) of about 1 minute. Fentanyl and sufentanil have equilibration half-lives of about 6 minutes.

8
Q

Dalam jangkauan normal dari auto regulasi, perubahan pada cerebral blood flow sebesar 1-mmHg dalam arterial carbon dioxide (PaC02), paling baik dapat dijelaskan sebagai :

A. 10-11 ml/100g/min
B. 4-5 ml/100g/min
C. 7-8 ml/100g/min
D. 1-2 ml/100g/min
E. 13-14 ml/100g/min
A

D. 1-2 ml/100g/min

There exist a linear relationship between cerebral blood flow and arterial carbon dioxide (PaC02) when the arterial PaC02 is between 20-80 mmHg. For every 1-mmHg change in PaC02 there is a 1-2 ml/100g/min change in arterial cerebral blood flow.